Tube-rolling mill



y 12, 0 A. I. TSELIKOV ETAL 3,511,070

TUBE-ROLLING MILL Filed July 31, 1967 United States Patent 3,511,070 TUBE-ROLLING MILL Alexandr Ivanovich Tselikov, Ulitsa Chernyakhovskogo 4, kv. 127, Moscow, U.S.S.R.; and Alexandr Borisovich Vernik, Prospekt Lenina 13, kv. 54; Vasily Makarovich Yampolsky, Ulitsa Pervomaiskaya 24, kv. 21; Iosif Lvovich Zayats, Ulitsa Zhulyabina 3, kv. 99; Igor Konstantinovich Tartakovsky, Prospekt Lenina 16, kv. 30; Petr Mikhailovich Finagin, Ulitsa Zhulabina 10, kv. 21; and Anatoly Alexandrovich Kovtushenko, Prospekt Lenina 20, kv. 20, all of Elektrostal, Moskovskoi oblast, U.S.S.R.; and Evgeny Alexandrovich Zhukevich-Stosha, Prospekt Mira 43, kv. 5; Vadim Anatolievich Verderevsky, Volgogradsky prospekt 171, kv. Gazis Kutuzovich Seifulin, Zelouodolskaya ulitsa 27, korpus 6, kv. 32; Arkady Iosifovich Grinshpun, Ulitsa Shaturskaya 39, kv. 80; and Valery Georgievich Balakin, Ulitsa Mosfilmovskaya 25, kv. 77, all of Moscow, U.S.S.R.; and Zelman Abelevich Sominsky, Ulitsa K. Marxa 5, kv. 3; and Matvei Borisovich Bisk, Ulitsa Baxova 7, kv. 7, both of Kamensk-Uralsk, U.S.S.R.; and Jury Vasilievich Petrov, Ulitsa Pobedy 10, kv. 54; and Zinovy Semenovich Volshonok, Ulitsa Sovetskaya 11/2, kv. 54, both of Elektrostal, Moskovskoi oblast, U.S.S.R.; and Evgeny Andreevich Volchkov, Domozhirovskaya Ulitsa 3, kv. 53, Nogiusk, Moskovskoi oblast, U.S.S.R.; and Vladimir Pavlovich Anisiforov, Ulitsa Sharikopodshipnikovskaya 2, kv. 98; and Rudolf Markovich Shpigelman, Ulitsa Junykh Lenintsev. 107, korpus 13, kv. 40, both of Moscow, U.S.S.R.

Filed July 31, 1967, Ser. No. 657,275 Claims priority, application U.S.S.R., Aug. 1, 1966, 1,095,636 Int. Cl. B21b 17/04 US. Cl. 72209 2 Claims ABSTRACT OF THE DISCLOSURE A tube-rolling mill comprises at least two coaxially disposed roll stands, in each of which there is provided a mandrel between a pair of rolls and a mandrel bar located behind the rolls and connected to each mandrel, there being fixing devices arranged in a line behind each roll stand for alternatively clamping each mandrel bar at its front and rear ends and rollers for moving a tube along the mandrel bars 'while their front ends are held in the respective fixing devices. A feeding device for receiving the whole tube is located between the roll stands to enable independent feed of the tubes into the rolls of the subsequent stand so that simultaneous rolling can be provided in both said roll stands. The feeding device comprises a roller table, whose length exceeds the length of the tube to be delivered thereto from the preceding roll stand, and at least one pair of push-rollers for the positive feeding of said tube into said subsequent roll stand.

The present invention relates to a tube-rolling installation for the manufacture of hot-rolled tubes, and more particularly to mills for rolling tubes in mandrels.

Widely known in the tube rolling practice are the installations of the Stiefel system, wherein a stand with obliquely disposed rolls, intended for piercing billets, is followed by an automatic mill ensuring a vigorous elongation of a tube in several passes.

The main disadvantage of such installations consists in the necessity of employing the reversing of a tube when rolling in the automatic mill, because the rolling operation is carried out in two to three passes, alternating with the reversal of the tube in an idle pass into its initial position.

This disadvantage causes great losses of working time, because 75 percent of the time in the rolling cycle is spent ice on performing auxiliary operations. This interferes with increasing the productive capacity of the rolling installation as a whole.

Attempts have been made to eliminate said disadvantages by designing the tube-rolling mill in such a manner that the rolling stands be disposed along a common rolling axis.

Thus, for example, there is known a tube-rolling mill, in which a tube is successively rolled in mandrels in two stands disposed along the same rolling axis. A mandrel bar is provided between the stands, carrying on its ends mandrels disposed between the rolls of the rolling stands. In the process of rolling, the mandrel bar is held by front and rear fixing devices that are operating alternatingly, each of which is located closely to the stand rolls. This mill enables the idle passes of tubes to be eliminated and their rolling to be effected along the same axis. In this case, however, only separate rolling can be effected, i.e. in the process of rolling of a tube in the subsequent rolling stand the preceding rolling stand cannot operate. This is conditioned by the fact that when rolling in the first rolling stand, the mandrel bar with the mandrel is first of all held by the rear fixing device being the most remote one from this stand until the tube completely emerges from the rolls. Then the mandrel bar is held by the front fixing device, disposed in the vicinity of the first rolling stand, while the rear fixing device, being the most remote one from this stand, releases the mandrel bar to permit the passage of the tube through the second rolling stand and remains in the open position until the process of rolling in the second stand is completed. Hence, the subsequent tube cannot be fed into the first stand because during the whole period of rolling in the second stand the front fixing device closes the outlet of the first stand, said fixing device holding the mandrel bar.

Among other disadvantages of this known tube-rolling mill, should be mentioned the impossibility of quickly eliminating disturbances inevitable during the hot rolling, such as, for example, the elimination of unfinished sections from one of the rolling stands; complicated designs of fixing devices that ensure both safe fixing of the mandrel bar in rolling and turning of the mandrel bar with the tube before feeding the latter into the subsequent rolling stand; and the ditficulty encountered when replacing the mandrels when necessary.

An object of the present invention is to provide such a tube-rolling mill which is simple in design and has a high productive capacity.

Another important object of the present invention is to provide a tube-rolling mill which is convenient in servicing.

A further important object of the present invention is to provide a tube-rolling mill which is reliable in operation.

In conformity with these and other objects, in the proposed tube-rolling mill, comprising at least two coaxially disposed rolling stands, in each of which between the rolls is disposed a mandrel, provided on a mandrel bar which is alternatingly held by the front and rear fixing devices, there is provided to the invention, a device for handling and feeding a tube into the subsequent rolling stand between the rear fixing device of the first stand and the subsequent rolling stand.

A preferable embodiment of the device for handling and feeding comprises a roller table, whose length exceeds the length of a tube delivered thereon from the preceding rolling stand, and at least one pair of push-rollers for the positive feeding of the tube into the subsequent rolling stand.

Such a design of the proposed tube-rolling mill allows, when the rolling stands are coaxially disposed, the rolling of tubes in one rolling stand to be effected independently of the operation of the other rolling stand, i.e. the successive rolling of a plurality of tubes to be effected simultaneously in all the rolling stands, which ensures a high productive capacity of the rolling mill.

Furthermore, in the case of operational disturbances which inevitably arise in hot rolling, any conventional means can be used to remove tubes from the roller table, and to return them into the production flow line if the tubes are considered to be suitable for subsequent rolling, which provides for a dependable and stable operation of the tube-rolling mill, and for a quick elimination of the consequences of the operation disturbances.

The possibility of mounting each mandrel on its own mandrel bar simplifies adjusting of the positioning of the mandrel and its replacement in the case of wear, which is considered to be very convenient in operation.

The nature of the present invention will become more fully apparent from a consideration of the following description of an exemplary embodiment thereof, taken in conjunction with the accompanying drawing, in which:

FIG. 1 is a longitudinal section of a tube-rolling mill according to the present invention;

FIG. 2 shows the mill at the instant where the tube, rolled in the preceding rolling stand, is delivered therefrom; and

FIG. 3 shows the mill at the instant where two tubes are simultaneously rolled in two coaxially disposed rolling stands.

The proposed tube-rolling mill comprises two coaxially disposed rolling stands 1 and 2 (FIG. 1), in each of which between rolls 3, 4 and 5, 6 respectively there are disposed respective mandrels 7 and 8, mounted on mandrel bars '9 and 10 that are alternatingly held at their front and rear ends respectively by the front fixing devices 11, 12 and rear fixing devices 13, 14.

Provided between the rear fixing device 13 and the rolling stand 2 is a device 15 for handling and feeding a tube into the subsequent rolling stand 2.

Thereby, each mandrel 7 and 8 can be mounted on separate mandrel bars 9 and 10, which simplifies replacing of the mandrels 7 and 8 and adjusting their positioning between the rolls 3, 4 and 5, 6.

The device 15 comprises a roller table 16, whose length a exceeds the length l of a tube '17 (FIG. 2), delivered thereon from the preceding rolling stand 1, and at least one pair of push-rollers 18 ensuring the positive feeding of the tube 17 into the subsequent rolling stand 2.

The exemplary embodiment of the invention features one pair of push-rollers 18 (FIG. 1) provided therein.

It is expedient to provide two pairs of such push-rollers to enable tubes of different length to be rolled.

Since the length a of the roller table 16 exceeds the length l of the tube 17, any existing means for the removal of the tube 17 from the roller table 16 can be disposed along the roller table 16, the tube being considered suitable for the subsequent rolling, and for its returning into the production line.

As is evident from FIG. 3, a simultaneous rolling of a tube 19 in the preceding rolling stand 1 and the tube 17 in the subsequent rolling stand 2 is ensured owing to the fact that provided between the rear fixing device '13 and the rolling stand 2 is the device 15 for handling and feeding the tube into the subsequent rolling stand 2, which is conductive to a considerable increase in the productive capacity of the tube-rolling mill.

Rollers 20 are employed for moving the tube 17 along the mandrel bar 9 (FIG. 2), the number of said rollers depending upon the length l of the tube being rolled.

The tube-rolling mill operates in the following manner.

All the mechanisms of the mill are brought into their initial positon, namely; the rear fixing devices 13 and 14 4- hold the mandrel bars 9 and 10 with the mandrels 7 and 8; the front fixing devices 11 and 12 are drawn apart to ensure the free delivery of the tubes 17 and 19 from the rolling stands 1 and 2, while the rollers 20 are also drawn apart.

The tube 17 (FIG. 1) to be rolled is fed into the rolling stand 1. On completing the process of rolling in the rolling stand 1, the front fixing device 11 clamps the mandrel bar 9, while the rear fixing device 13 releases the mandrel bar 9 in order to permit the free passage of the tube 17 through the zone of the rear fixing device 13.

Thereafter, the rollers 20 are drawn together, and the tube 17 is moved along the mandrel bar 9 beyond the rear fixing device 13 onto the device 15 for handling and feeding the tube 17 into the subsequent rolling stand 2. The tube 17 is handled by means of the roller table 16, whereupon the push-rollers 18 (FIG. 3) are employed to effect the positive feed of the tube into the rolling stand 2, which provides for the firm gripping of the tube 17 by the rolls 5 and 6 of the rolling stand 2.

As soon as the rear end of the tube 17 passes through the zone of the rear fixing device 13, the latter fixes the mandrel bar 9 with the mandrel 7 in its initial position. Immediately thereafter the front fixing device 11 releases the mandrel bar 9, and the subsequent tube 19 (FIG. 3) is fed into the rolling stand 1. At the same time, the preceding tube 17 is fed, as has been noted hereinbefore, into the rolling stand 2. The simultaneous rolling of one tube 17 in the subsequent rolling stand 2, and of the second tube 19 in the preceding rolling stand thus occurs. When rolling the tube 17 in the rolling stand 2 and the tube 19 in the rolling stand 1, the operation of all the devices is effected in a manner similar to that as has been described hereinbefore in the case of the tube 17 (FIG. 1) being rolled in the stand 1.

What is claimed is:

1. A tube-rolling mill comprising at least two coaxially disposed rolling stands each with a pair of rolls; mandrel bars with mandrels disposed between the rolls of each rolling stand; each bar having a front and a rear end, first and second fixing means at the front and rear end of each mandrel bar for alternately engaging and fixing the same, means for moving a tube to be rolled along each said mandrel bar from the front to the rear thereof, the latter means being mounted between said first and second fixing means of the associated bar, and a device for handling and feeding the tube disposed between successive stands for feeding the tube from the previous stand to the subsequent stand, said device being located between said fixing means at the rear end of the previous stand and the fixing means at the front end of the subsequent rolling stand to permit independent feeds of tubes to the respective stands with simultaneous rolling of the tubes therein.

2. A tube-rolling mill according to claim 1 wherein the device for handling and feeding a tube into the subsequent rolling stand comprises a roller table having a length which exceeds the length of the tube to be delivered thereto from the previous rolling stand, and at least one pair of push-rollers for the positive feeding of said tube to said subsequent rolling stand.

References Cited UNITED STATES PATENTS 774,796 11/ 1904 Stiefel 72209 961,818 6/1910 Stuting 72209 988,569 4/1911 Harkness 72209 3,349,468 10/1967 Farber 72209 MILTON S. MEHR, Primary Examiner 

